Telephone.



W. W. DEAN.

TELEPHONE.

APPLIOATION FILED AUG. 9, 1909.

1,036,,05, Patented Aug. 27, 1912.

HA5 AUTO/7 ey UNITED STATES PATENT OFFICE.

WILIJIAM W. DEAN, OF ELYRIA, OHIO, ASSIGNOR TO THE DEAN ELECTRIC COMPANY,

" F ELYRIA. OHIO, A CORPORATION OF OHIO.

I TELEPHONE.

Specification of Letters latent.

Application filed August 9, 1909. Serial No. 511,982.

I citizen -'of the United States, :residing at jects upward from the bottom of the recep Elyria, in the county of Lorain and'State of Ohio, have invented-"certain new and-useful Improvements in Telephones; andI do; hereby declare the following to be a full, clear, and exact description of'the :inven-- tion,-sueh as will enable others skilled in the art to which it appertains tozmake' and use the same. I

This invention relates to magnetic tele-' phones-and more particularly to telephone receiversybut the utility thereof is-notlimited to -such ia:purpose, as among other uses 1 may apply it as a transmitter.

I have produced an improved receiver b providing a magnetic circuit of very :low reluctance and one acting on the receiver diaphragm in such a way that I am able'to employ-an electremagnet coil of low resistance. To accomplish-this, :I haveprovided a plurality of U-shaped soft iron wires arranged so one-of the limbs -'of each wire forms an element of'theperiphery of a cup shaped receptacle, while the other:limb-protacle forming an element of the magnet core. I also endeavor to distribute the attraction between the magnet and the diaphragm over the surface of the whole and to make the' same more uniform than with the telephone receivers now in use. .To accomplish this, I may arrange the exterior ends of the flux conductors in a continuous circuit around the exterior of the magnet as illustrated in the drawing. 7 I also endeavor to provide a devicev of this character, which may be cheaply and easily constructed, and to this end I set the magnet coil within the cup and over the core. The whole is then placed within a second cup and the interstices among the various parts filled with a liquid insulating 'material, which solidifies, insulating the various parts from one another. While I have thus described my purposes and briefly the mode of realizing them, I do not desire to be limited thereby.

My invention will behest understood by referring to the following description when taken in connection with the accompanying drawings, showing one specific embodiment thereof, while the scope may be more articularly pointed out in the a pended claims.

Figure 1 is a cross section of my improved telephone receiver showingthe -va-' rious parts. Fig. 2 is an end elevation of the receiver cup with thefdiaphragm removed.

with the ear piece 2 screwed thereon. 'Within this shell I inclose a receiver cup 3. The

bottom forms a. base piece at the ear end of the cup and thering 4 screws on clamping the diaphragm 5 between this and the cup. An insulated piece 6 is attached to the outside of the bottom of the cup and carrice the terminals 7 and 8. iTheterminals ofzthe electroamagnet are shown-connected at 9 and 10 to the terminals 8 and :7. A

Patented. Aug. 27,1912.

cup 11'is fastened to the bottom of-the=receiver cup and on the inside thereof. A

plurality of=elements 12 0f softiron, or

ether high flux conducting material, are doubledo-ver and assembled in such a Way that the outside ends form a cup shaped receptaclewhi'le'the inside elements, or limbs project upward at the center forming a core for an electromagnet. The ."periphery of the cup 'is shownat 14 and-may be formed of several layers of these =fluxvconductors. An electromagnet coil 15 is then placed over the core and within the receptacle,.and these terminals connected to 7 an 8 as previously described. The spool head is shown at 16, a layer of rigid material 17 on top of the head 16 and between the projecting ends of the flux conducting elements. Screw 20 projects through the bottom of the receiver cup into the bottom of the second cup at taching the same thereto.

In producing my apparatus, I proceed by the following methodz -The wires, or flux conductors are doubled over and arranged as described into a cup shaped. member with the core projecting from the center. The electromagnet coil is placed over the core and within the cup and the whole inserted into another cup. Aliquid insulating material is then poured over the whole until the interstices are filled and a layer is accumulated on top of the spool head up to the of the outside cup. When this solidifies 1t furnishes a backingfor the wires, which may be then trimmed ofl even with the rim of the cup and the layer of sol1dified insulating material. The interstices between the flux conductors are thus lled with an insulating material which thoroughly insulates them one from another andprevents the flow of any eddy currents in the magnetic circuit. The spaces between the wires are 6 filled in, increasing the insulation there between and the whole is rendered compact and solid. I thus produce a highly efiicient receiver which attracts the diaphragm at the center and atpoints equally distant there- 1 from on the periphery of a circle. This prevents any buckling or tendency of. the

bottom to sag along a line, as sometimes oc-.

curs with receivers which are controlled by a horse-shoe shaped magnet, The device is also easily manufactured as will be clear to those skilledjn the art from the description of the method of manufacturing the same.

While I have shown the telephonein this particular preferred embodiment, it will be obvious to those skilled in the art that numerous and\ extensive departures from the forms and"'detail. of the apparatus here shown, may be made without departing from the spirit of this invention, the same i being herein shown solely for the purpose of lear y illustrating one specific embodiment thereof.

I claim: I ,a 1. In a telephone recelver, the combina;

tion ofa base, a cup supported on said base,

a magnet spool within said cup, a magnet coil wound thereon, circuit connections for said coil, adiaphragm supported in proximity to said magnet, said diaphragm free to vibrate in response to said magnet, a plurality of soft iron flux conductors forming thecore of said magnet coil, said'flux conductors being insulated from one another, a

return flux circuit of said magnet coil, the ends of said conductors extending beyond the magnet coil at both ends and a layer of solid "material over the magnet spool and between the ends of the flux conductors, the

ends of the flux conductors extending to the top of-said layer of solid material.

2., In a telephone receiver, the combination of a receiver shell, a base mounted in said shell, a cup removably'fastened to said base, a plurality of magnetic metal flux con- 'ductors bent into U-shapes in said cup, one

limb of each flux conductor'being in proximity to the edge of the cup and forming an center and inside the limbs at the sides, a

coil on said spool, terminals for said coil conductors leading to said terminals, the ends of the flux conductors extending beyond the end of the "spool, insulating-mate- Vrial poured between the flux conductors, a

layer of insulating material on top of said spool and between the projecting ends of the flux conductors, the ends of the flux conductors projecting-rte the top of said layer, a vibratile diap agm adapted to be actuated by said magnet and means to clamp the edges ofsaid diaphragm to said base.

In testimon whereof I afiix my signature in presence 0 two witnesses.- a we '-WILLIAM W. DEAN, Witnesses:

D. A. GLovnR, F. O. RICHEY. 

